Piezoelectric Airflow Sensor

Docket: UAH-P-14018

Technology

Traditional flow sensors have utilized different sensing principles such as thermal anemometry, indirect inference from pressure differences through the Coriolis effect, and wall shear forces. However, common techniques such as hot-wire anemometry often do not accurately measure low flow velocities and directions. More accurate techniques like Laser Doppler Velocimetry (LDV) tend to be complex, bulky, and expensive, rendering them impractical for nonscientific and engineering purposes.

Researchers at UAH are currently in the early stages of developing a Piezoelectric Airflow Sensor (PAS) system that detects airflow magnitude and direction. The PAS is a bio-mimetic of tubercles found in nature and it relates the voltage collected by piezoelectric materials due to flow-induced vibration to airflow characteristics. It can be simply mounted on any surface or remotely-operated small air vehicle to conduct airflow surveys, and the measurements can be wirelessly transmitted to the host platform.

The expected airspeed measurement ranges from 1 to 50 knots (1.2 to 57.5 mph) with an accuracy of around 0.1 knots (0.12 mph). Its low cost, small size, and light weight allow for a three-axis and array design to capture the entire flow field, increase sensitivity, and eliminate undesired signals.